T-minus 15 days until primary voters head to the polls. But for undecided Democrats torn between seven-term incumbent Bill Sorrell and “change” agent TJ Donovan, there are still plenty of chances left for a side-by-side comparison.

The candidates will go toe-to-toe in at least five more debates, starting with their dual radio appearance on WDEV’s The Mark Johnson Show at 9 a.m. this morning.

On Wednesday, alt-weekly Seven Days and the Chittenden County public access outlet, Channel 17, will co-host a debate at 5 p.m. in Burlington City Hall. The event will air on Channel 17, and viewers can also stream it live at 7dvt.com.

On Thursday, the Burlington Free Press conducts “Part 1” of its Sorrell/Donovan debate, and will stream the proceedings on its website. “Part 2” arrives on Tuesday, Aug. 21. And the candidates meet again on Thursday, Aug. 23 on Vermont Public Radio’s “Vermont Edition.”

The pace of this closely watched political horse race has quickened as the campaigns enter the final stretch running neck and neck. The contest saw its first mass media expenditure last week when a political action committee called “The Committee for Fairness and Justice” began airing pro-Sorrell ads on major television networks.

According to a report by Taylor Dobbs at VTDigger.com, the group, funded chiefly by the Democratic Attorney Generals Association, will spend nearly $99,000 on the television spots.

Donovan convened a press conference to condemn the independent expenditures from an out-of-state special interest group. Sorrell responded by saying that, in light of a 2010 U.S. Supreme Court decision that opened the door to unlimited spending by outside groups, there’s nothing illegal about the ads. Anyway, Sorrell said, he has no communication with or control over the Committee for Fairness and Justice. Independent expenditure groups are by law prohibited from coordinating with candidates.

Donovan doesn’t have any well-funded groups pouring six-figure amounts into his candidacy. But he’s looking to secure votes in northern Vermont by adding to raft of endorsements he’s picked up over the summer.

Following a morning press conference in St. Albans last Tuesday at which he received endorsements from mayors past and present, TJ Donovan unveiled a prescription drug plan that he says will serve as “a cornerstone policy of his campaign.”

St. Albans has become a poster city for Vermont’s prescription drug problem, with local officials attributing chronic public-safety issues to rampant opiate abuse. Former St. Albans mayors Peter Deslauriers and Martin Manahan, as well as current mayor, Liz Gamache, all formally endorsed Donovan.

You might remember Manahan from the 2010 cycle, when the Democrat enthusiastically endorsed Republican Brian Dubie. Manahan was so hot on Shumlin’s rival that he was featured in a 30-second TV spot entitled “Democrats for Dubie.”

“The last thing Brian cares about is what party I belong to,” Manahan said in the ad. “He cares about our community and the state of Vermont.”

This year, Manahan is a Democrat for Donovan.

“TJ has fought alongside us in the battle against the number one criminal activity our state is facing,” Manahan said in a release from the Donovan campaign. “We need an Attorney General that has not lost the connection to our local communities.”

Manahan had some rough words for Bill Sorrell, who has, according the former mayor, been a no-show in St. Albans, despite the city’s well-chronicled narcotics woes.

“I was disappointed that during my six years as mayor, I never had any contact from Attorney General Sorrell,” Manahan said. “I think the highest ranking member in the Vermont law enforcement community should have offered his support in our efforts fighting the prescription drug epidemic our community was facing.”

Manahan’s comments, and the Donovan campaign’s decision to feature them so prominently in a press release, spotlight the challenger’s newfound willingness to go more directly after Sorrell’s record.

The release came literally one day after Donovan, at Sorrell’s behest, signed a “positive campaign pledge.”

In doing so, Donovan has vowed not to “engage in, permit or condone any negative or defamatory attacks upon my opponent’s character.” Donovan looks to be on safe ground here, with Manahan’s jab directed at Sorrell’s job as AG, not his constitution as a human being.

“We can corroboratively rebuild our criminal justice system with a foundational rock of treatment, not the shifting sands of incarceration,” says the plan, which can be read in its entirety at vermontpressbuerau.com.

Donovan also picked up an endorsement from the Vermont Association of Realtors.

After losing out to Donovan on endorsements from the sheriffs and state troopers, Sorrell finally managed to pad his law enforcement bona fides with a nod from the state’s largest police organization.

The Vermont Police Association, which represents more than 850 sworn law enforcement officers at the local, state and federal levels, doesn’t customarily issue endorsements in primaries, according to Sorrell campaign. But according to association president George Fon, Sorrell’s campaign said, “this year was an exception and the membership wished to take a stand in this important election.”

Stay tuned this week as they near the finish line in what at this point looks to be anyone’s race.